Grayscale Image

Turning a photo black and white seems simple, yet the way colors are mapped to grays changes the picture completely. A red rose against green leaves can become a vivid contrast or two nearly identical grays. This tool offers several conversion methods, including simulations of the color filters film photographers used, plus contrast and brightness controls.

Natural luminance

The default method weights red, green and blue the way the human eye perceives brightness, with green counting most and blue least. It calculates in linear light, the physical intensity before screen gamma, which keeps the tonal relationships faithful. For most photos this gives the most natural-looking result, close to what you would expect when imagining the scene without color.

Average and lightness

“Average of R, G and B” treats the three channels equally. It is simple and predictable, used in some technical and teaching contexts, but blues tend to look too bright. “Lightness” takes the midpoint between the strongest and weakest channel, which matches the L of the HSL color model; it tends to be lower in contrast. Both are included so you can match what other software produces.

Black-and-white film filters

Film photographers screwed colored filters onto the lens to control how colors turned into grays. A red filter blocks blue light, so blue skies become dark and clouds pop; it also smooths skin and lightens lips. Orange is a softer version, flattering for portraits. Yellow gives a slight sky darkening and is the classic landscape default. Green lightens foliage and darkens red tones, useful for nature and for adding character to faces. Blue raises haze and darkens skin, recreating the look of very early photographic plates.

Single channels

Selecting one channel uses only the red, green or blue values. The red channel often gives smooth portraits, the green channel is detailed, and the blue channel is noisy but atmospheric. Inspecting the channels this way also helps you understand why the film filters behave as they do.

Contrast and brightness

After conversion, a black-and-white image often benefits from extra contrast, because color differences no longer separate elements. Increase contrast until the darkest areas are near black and the brightest near white without losing detail. Use brightness to shift the overall mood toward high-key or low-key.

Preview, compare and save

The preview runs on a reduced copy for fast feedback; the compare switch shows the original. Downloading processes the full-resolution image. JPG is the usual choice for photos, PNG for graphics and transparent images, WebP for websites.

Tips for strong monochrome images

Look for scenes with clear light and shadow, textures and shapes rather than color contrast. Portraits in soft window light, architecture, street scenes and stormy skies are classic subjects. Add a subtle vignette afterwards with the Photo Vignette Effect to draw the eye to the center.

Keep the color original

A black-and-white version is a new file; the color photo is not changed. Keep the original, since you may want a different filter later or a color version for another use.

Related tools

For a warm, old-fashioned tone, try the Sepia Photo Filter. For two-color toning of shadows and highlights, use Split Tone Image. To convert entire documents, see Grayscale PDF.